A Saudi prince has been jailed for life by a British court after he was found guilty of murdering his male servant in a brutal attack at a London hotel.

Saud Abdulaziz bin Nasser al-Saud, the grandson of Saudi Arabia's King Abdullah, was ordered to serve a minimum of 20 years in prison by a judge at London's Central Criminal court on Wednesday.

"It is very unusual for a prince to be in the dock on a murder charge. No one in this country is above the law," David Bean, the judge, told Saud as he handed down the sentence.

"It would be wrong for me to sentence you either more severely or more leniently because of your membership of the Saudi royal family," he added.

On Tuesday the court convicted 34-year-old al Saud of beating and strangling Bandar Abdullah Abdulaziz to death at London's Landmark hotel in February this year.

'Sexual element'

The prosecution had argued that the 32-year-old was murdered following a lengthy campaign of violence against him.

Jonathan Laidlaw, the prosecutor, said the prince had abused his aide in the past, showing jurors a video shot in the Landmark's elevator which appears to show the prince battering the man.

He added that photographs of Abdulaziz stored on a mobile phone "plainly proved" that there was a "sexual element" to the abuse.

"Beneath the surface this was a deeply abusive relationship which the defendant exploited, as the assaults in the lift so graphically demonstrate, for sadistic reasons, for his own personal gratification," Laidlaw told the court.

Abdulaziz was found to have suffered bleeding in the brain, a fractured larynx and bruising in the abdomen. Pathologists said the extent of injuries meant they could not say for certain what caused his death.

The jury had heard that the prince bit his victim hard on both cheeks during his murderous attack at their suite.

The suggestion of a sexual element in the murder could mean al Saud faces the possibility of execution if he returns to Saudi Arabia, where being gay is a capital offence.

Al-Saud had attempted to claim diplomatic immunity when he was first arrested earlier this year.